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			<h1>Java 流(Stream)、文件(File)和IO</h1>
<p>Java.io 包几乎包含了所有操作输入、输出需要的类。所有这些流类代表了输入源和输出目标。
</p><p>Java.io 包中的流支持很多种格式，比如：基本类型、对象、本地化字符集等等。
</p><p>一个流可以理解为一个数据的序列。输入流表示从一个源读取数据，输出流表示向一个目标写数据。
</p><p>Java 为 I/O 提供了强大的而灵活的支持，使其更广泛地应用到文件传输和网络编程中。
</p><p>但本节讲述最基本的和流与 I/O 相关的功能。我们将通过一个个例子来学习这些功能。
</p><hr><h2>读取控制台输入</h2>

<p>
Java 的控制台输入由 System.in 完成。
</p><p>为了获得一个绑定到控制台的字符流，你可以把 System.in 包装在一个 BufferedReader 对象中来创建一个字符流。
</p><p>下面是创建 BufferedReader 的基本语法：</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">BufferedReader</span><span class="hl-code"> </span><span class="hl-identifier">br</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">BufferedReader</span><span class="hl-brackets">(</span><span class="hl-reserved">new</span><span class="hl-code"> 
                      </span><span class="hl-identifier">InputStreamReader</span><span class="hl-brackets">(</span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">in</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;</span></div>
</div>
</div>
<p>BufferedReader 对象创建后，我们便可以使用 read() 方法从控制台读取一个字符，或者用 readLine() 方法读取一个字符串。
</p><hr><h2>从控制台读取多字符输入</h2>
<p>
从 BufferedReader 对象读取一个字符要使用 read() 方法，它的语法如下：
</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">read</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-reserved">throws</span><span class="hl-code"> </span><span class="hl-identifier">IOException</span></div>
</div>
</div>
<p>每次调用 read() 方法，它从输入流读取一个字符并把该字符作为整数值返回。 当流结束的时候返回 -1。该方法抛出 IOException。
</p><p>下面的程序示范了用 read() 方法从控制台不断读取字符直到用户输入 <span class="marked">q</span>。</p>
<div class="example">
<h2 class="example">BRRead.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">//</span><span class="hl-comment">使用 BufferedReader 在控制台读取字符</span><span class="hl-comment"></span><span class="hl-code">
 
</span><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.*;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">BRRead</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-reserved">throws</span><span class="hl-code"> </span><span class="hl-identifier">IOException</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-types">char</span><span class="hl-code"> </span><span class="hl-identifier">c</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 使用 System.in 创建 BufferedReader</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-identifier">BufferedReader</span><span class="hl-code"> </span><span class="hl-identifier">br</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">BufferedReader</span><span class="hl-brackets">(</span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">InputStreamReader</span><span class="hl-brackets">(</span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">in</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">输入字符, 按下 'q' 键退出。</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 读取字符</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-reserved">do</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-types">char</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-identifier">br</span><span class="hl-code">.</span><span class="hl-identifier">read</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">c</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">while</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">c</span><span class="hl-code"> != </span><span class="hl-quotes">'</span><span class="hl-string">q</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>以上实例编译运行结果如下:</p>
<pre>
输入字符, 按下 'q' 键退出。
runoob
r
u
n
o
o
b


q
q
</pre>
<hr><h2>从控制台读取字符串</h2>
<p>
从标准输入读取一个字符串需要使用 BufferedReader 的 readLine() 方法。
</p><p>它的一般格式是：
</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">readLine</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-reserved">throws</span><span class="hl-code"> </span><span class="hl-identifier">IOException</span></div>
</div>
</div>
<p>
下面的程序读取和显示字符行直到你输入了单词"end"。
</p>
<div class="example">
<h2 class="example">BRReadLines.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">//</span><span class="hl-comment">使用 BufferedReader 在控制台读取字符</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.*;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">BRReadLines</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-reserved">throws</span><span class="hl-code"> </span><span class="hl-identifier">IOException</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-comment">//</span><span class="hl-comment"> 使用 System.in 创建 BufferedReader</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-identifier">BufferedReader</span><span class="hl-code"> </span><span class="hl-identifier">br</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">BufferedReader</span><span class="hl-brackets">(</span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">InputStreamReader</span><span class="hl-brackets">(</span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">in</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">str</span><span class="hl-code">;
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Enter lines of text.</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Enter 'end' to quit.</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-reserved">do</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">str</span><span class="hl-code"> = </span><span class="hl-identifier">br</span><span class="hl-code">.</span><span class="hl-identifier">readLine</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">str</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">while</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code">!</span><span class="hl-identifier">str</span><span class="hl-code">.</span><span class="hl-identifier">equals</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">end</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>以上实例编译运行结果如下:</p>
<pre>
Enter lines of text.
Enter 'end' to quit.
This is line one
This is line one
This is line two
This is line two
end
end
</pre>
<blockquote>
<p>JDK 5 后的版本我们也可以使用 <a href="../java/java-scanner-class.html" target="_blank" rel="noopener">Java Scanner</a> 类来获取控制台的输入。</p></blockquote>


<h2>控制台输出</h2>
<p>
在此前已经介绍过，控制台的输出由 print( ) 和 println() 完成。这些方法都由类 PrintStream 定义，System.out 是该类对象的一个引用。
</p><p>PrintStream 继承了 OutputStream类，并且实现了方法 write()。这样，write() 也可以用来往控制台写操作。
</p><p>PrintStream 定义 write() 的最简单格式如下所示：</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">write</span><span class="hl-brackets">(</span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">byteval</span><span class="hl-brackets">)</span></div>
</div>
</div>
<p>该方法将 byteval 的低八位字节写到流中。
</p>
<h3>实例</h3>
<p>
下面的例子用 write() 把字符 "A" 和紧跟着的换行符输出到屏幕：
</p>
<div class="example">
<h2 class="example">WriteDemo.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.*;
 
</span><span class="hl-comment">//</span><span class="hl-comment">演示 System.out.write().</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">WriteDemo</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code">;
        </span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-quotes">'</span><span class="hl-string">A</span><span class="hl-quotes">'</span><span class="hl-code">;
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">write</span><span class="hl-brackets">(</span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">write</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-special">\n</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>运行以上实例在输出窗口输出 "A" 字符</p>
<pre>
A
</pre>
<p><strong>注意：</strong>write() 方法不经常使用，因为 print() 和 println() 方法用起来更为方便。
</p>
<hr><h2>读写文件</h2>
<p>
如前所述，一个流被定义为一个数据序列。输入流用于从源读取数据，输出流用于向目标写数据。
</p><p>下图是一个描述输入流和输出流的类层次图。</p>
<p>
<a href="../wp-content/uploads/2013/12/iostream2xx.png" target="_blank" rel="noopener"><img decoding="async" src="https://www.runoob.com/wp-content/uploads/2013/12/iostream2xx.png" /></a></p>
<p>下面将要讨论的两个重要的流是 <strong>FileInputStream</strong> 和 <strong>FileOutputStream</strong>。
</p><hr>
<h2>FileInputStream</h2>
<p>该流用于从文件读取数据，它的对象可以用关键字 new 来创建。
</p><p>有多种构造方法可用来创建对象。
</p><p>可以使用字符串类型的文件名来创建一个输入流对象来读取文件：</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">InputStream</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileInputStream</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">C:/java/hello</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;</span></div>
</div>
</div>
<p>也可以使用一个文件对象来创建一个输入流对象来读取文件。我们首先得使用 File() 方法来创建一个文件对象：
</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">C:/java/hello</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-identifier">InputStream</span><span class="hl-code"> </span><span class="hl-identifier">in</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileInputStream</span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-brackets">)</span><span class="hl-code">;</span></div>
</div>
</div>
<p>创建了InputStream对象，就可以使用下面的方法来读取流或者进行其他的流操作。</p>
<table class="reference">
	<tbody>
		<tr>
			<th style="width:44px;">
				<strong>序号</strong></th>
			<th style="width:533px;">
				<strong>方法及描述</strong></th>
		</tr>
		<tr>
			<td style="width:44px;">
				1</td>
			<td style="width:533px;">
				<strong>public void close() throws IOException{}</strong><br>
				关闭此文件输入流并释放与此流有关的所有系统资源。抛出IOException异常。</td>
		</tr>
		<tr>
			<td style="width:44px;">
				2</td>
			<td style="width:533px;">
				<strong>protected void finalize()throws IOException {}</strong><br>
				这个方法清除与该文件的连接。确保在不再引用文件输入流时调用其 close 方法。抛出IOException异常。</td>
		</tr>
		<tr>
			<td style="width:44px;">
				3</td>
			<td style="width:533px;">
				<strong>public int read(int r)throws IOException{}</strong><br>
				这个方法从 InputStream 对象读取指定字节的数据。返回为整数值。返回下一字节数据，如果已经到结尾则返回-1。</td>
		</tr>
		<tr>
			<td style="width:44px;">
				4</td>
			<td style="width:533px;">
				<strong>public int read(byte[] r) throws IOException{}</strong><br>
				这个方法从输入流读取r.length长度的字节。返回读取的字节数。如果是文件结尾则返回-1。</td>
		</tr>
		<tr>
			<td style="width:44px;">
				5</td>
			<td style="width:533px;">
				<strong>public int available() throws IOException{}</strong><br>
				返回下一次对此输入流调用的方法可以不受阻塞地从此输入流读取的字节数。返回一个整数值。</td>
		</tr>
	</tbody>
</table>
<p>除了 InputStream 外，还有一些其他的输入流，更多的细节参考下面链接：</p>
<ul>
<li>
<a href="../java/java-bytearrayinputstream.html" target="_blank" rel="noopener">ByteArrayInputStream</a></li><li>
<a href="../java/java-datainputstream.html" target="_blank" rel="noopener">DataInputStream</a></li>
</ul>
<hr><h2>
FileOutputStream</h2><p>
该类用来创建一个文件并向文件中写数据。</p><p>
如果该流在打开文件进行输出前，目标文件不存在，那么该流会创建该文件。</p><p>
有两个构造方法可以用来创建 FileOutputStream 对象。</p><p>
使用字符串类型的文件名来创建一个输出流对象：</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">OutputStream</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileOutputStream</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">C:/java/hello</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span></div>
</div>
</div>
<p>也可以使用一个文件对象来创建一个输出流来写文件。我们首先得使用File()方法来创建一个文件对象：
</p>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">C:/java/hello</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-identifier">OutputStream</span><span class="hl-code"> </span><span class="hl-identifier">fOut</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileOutputStream</span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-brackets">)</span><span class="hl-code">;</span></div>
</div>
</div>
<p>
创建OutputStream 对象完成后，就可以使用下面的方法来写入流或者进行其他的流操作。
</p>
<table class="reference">
	<tbody>
		<tr>
			<th style="width:47px;">
				<strong>序号</strong></th>
			<th style="width:529px;">
				<strong>方法及描述</strong></th>
		</tr>
		<tr>
			<td style="width:47px;">
				1</td>
			<td style="width:529px;">
				<strong>public void close() throws IOException{}</strong><br>
				关闭此文件输入流并释放与此流有关的所有系统资源。抛出IOException异常。</td>
		</tr>
		<tr>
			<td style="width:47px;">
				2</td>
			<td style="width:529px;">
				<strong>protected void finalize()throws IOException {}</strong><br>
				这个方法清除与该文件的连接。确保在不再引用文件输入流时调用其 close 方法。抛出IOException异常。</td>
		</tr>
		<tr>
			<td style="width:47px;">
				3</td>
			<td style="width:529px;">
				<strong>public void write(int w)throws IOException{}</strong><br>
				这个方法把指定的字节写到输出流中。</td>
		</tr>
		<tr>
			<td style="width:47px;">
				4</td>
			<td style="width:529px;">
				<strong>public void write(byte[] w)</strong><br>
				把指定数组中w.length长度的字节写到OutputStream中。</td>
		</tr>
	</tbody>
</table>
<p>除了OutputStream外，还有一些其他的输出流，更多的细节参考下面链接：</p>
<ul>
<li>
<a href="../java/java-bytearrayoutputstream.html" target="_blank" rel="noopener">ByteArrayOutputStream</a></li><li>
<a href="../java/java-dataoutputstream.html" target="_blank" rel="noopener">DataOutputStream</a></li></ul>
<h3>实例</h3>
<p>
下面是一个演示 InputStream 和 OutputStream 用法的例子：
</p>
<div class="example">
<h2 class="example">fileStreamTest.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.*;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">fileStreamTest</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-reserved">try</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-types">byte</span><span class="hl-code"> </span><span class="hl-identifier">bWrite</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> = </span><span class="hl-brackets">{</span><span class="hl-code"> </span><span class="hl-number">11</span><span class="hl-code">, </span><span class="hl-number">21</span><span class="hl-code">, </span><span class="hl-number">3</span><span class="hl-code">, </span><span class="hl-number">40</span><span class="hl-code">, </span><span class="hl-number">5</span><span class="hl-code"> </span><span class="hl-brackets">}</span><span class="hl-code">;
            </span><span class="hl-identifier">OutputStream</span><span class="hl-code"> </span><span class="hl-identifier">os</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileOutputStream</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">test.txt</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-reserved">for</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">x</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">; </span><span class="hl-identifier">x</span><span class="hl-code"> &lt; </span><span class="hl-identifier">bWrite</span><span class="hl-code">.</span><span class="hl-identifier">length</span><span class="hl-code">; </span><span class="hl-identifier">x</span><span class="hl-code">++</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                </span><span class="hl-identifier">os</span><span class="hl-code">.</span><span class="hl-identifier">write</span><span class="hl-brackets">(</span><span class="hl-identifier">bWrite</span><span class="hl-brackets">[</span><span class="hl-identifier">x</span><span class="hl-brackets">]</span><span class="hl-brackets">)</span><span class="hl-code">; </span><span class="hl-comment">//</span><span class="hl-comment"> writes the bytes</span><span class="hl-comment"></span><span class="hl-code">
            </span><span class="hl-brackets">}</span><span class="hl-code">
            </span><span class="hl-identifier">os</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
 
            </span><span class="hl-identifier">InputStream</span><span class="hl-code"> </span><span class="hl-identifier">is</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileInputStream</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">test.txt</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">size</span><span class="hl-code"> = </span><span class="hl-identifier">is</span><span class="hl-code">.</span><span class="hl-identifier">available</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
 
            </span><span class="hl-reserved">for</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">i</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">; </span><span class="hl-identifier">i</span><span class="hl-code"> &lt; </span><span class="hl-identifier">size</span><span class="hl-code">; </span><span class="hl-identifier">i</span><span class="hl-code">++</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-brackets">(</span><span class="hl-types">char</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-identifier">is</span><span class="hl-code">.</span><span class="hl-identifier">read</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string">  </span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-brackets">}</span><span class="hl-code">
            </span><span class="hl-identifier">is</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">catch</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">IOException</span><span class="hl-code"> </span><span class="hl-identifier">e</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Exception</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-brackets">}</span><span class="hl-code">
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>上面的程序首先创建文件test.txt，并把给定的数字以二进制形式写进该文件，同时输出到控制台上。
</p>
<p>以上代码由于是二进制写入，可能存在乱码，你可以使用以下代码实例来解决乱码问题：</p>
<div class="example">
<h2 class="example">fileStreamTest2.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">//</span><span class="hl-comment">文件名 :fileStreamTest2.java</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.*;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">fileStreamTest2</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-reserved">throws</span><span class="hl-code"> </span><span class="hl-identifier">IOException</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
 
        </span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">a.txt</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">FileOutputStream</span><span class="hl-code"> </span><span class="hl-identifier">fop</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileOutputStream</span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 构建FileOutputStream对象,文件不存在会自动新建</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">OutputStreamWriter</span><span class="hl-code"> </span><span class="hl-identifier">writer</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">OutputStreamWriter</span><span class="hl-brackets">(</span><span class="hl-identifier">fop</span><span class="hl-code">, </span><span class="hl-quotes">&quot;</span><span class="hl-string">UTF-8</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 构建OutputStreamWriter对象,参数可以指定编码,默认为操作系统默认编码,windows上是gbk</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">writer</span><span class="hl-code">.</span><span class="hl-identifier">append</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">中文输入</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 写入到缓冲区</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">writer</span><span class="hl-code">.</span><span class="hl-identifier">append</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-special">\r</span><span class="hl-special">\n</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 换行</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">writer</span><span class="hl-code">.</span><span class="hl-identifier">append</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">English</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 刷新缓存冲,写入到文件,如果下面已经没有写入的内容了,直接close也会写入</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">writer</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 关闭写入流,同时会把缓冲区内容写入文件,所以上面的注释掉</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">fop</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 关闭输出流,释放系统资源</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">FileInputStream</span><span class="hl-code"> </span><span class="hl-identifier">fip</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">FileInputStream</span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 构建FileInputStream对象</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">InputStreamReader</span><span class="hl-code"> </span><span class="hl-identifier">reader</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">InputStreamReader</span><span class="hl-brackets">(</span><span class="hl-identifier">fip</span><span class="hl-code">, </span><span class="hl-quotes">&quot;</span><span class="hl-string">UTF-8</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 构建InputStreamReader对象,编码与写入相同</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">StringBuffer</span><span class="hl-code"> </span><span class="hl-identifier">sb</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">StringBuffer</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-reserved">while</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">reader</span><span class="hl-code">.</span><span class="hl-identifier">ready</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">sb</span><span class="hl-code">.</span><span class="hl-identifier">append</span><span class="hl-brackets">(</span><span class="hl-brackets">(</span><span class="hl-types">char</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-identifier">reader</span><span class="hl-code">.</span><span class="hl-identifier">read</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-comment">//</span><span class="hl-comment"> 转成char加到StringBuffer对象中</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-brackets">}</span><span class="hl-code">
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">sb</span><span class="hl-code">.</span><span class="hl-identifier">toString</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">reader</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 关闭读取流</span><span class="hl-comment"></span><span class="hl-code">
 
        </span><span class="hl-identifier">fip</span><span class="hl-code">.</span><span class="hl-identifier">close</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 关闭输入流,释放系统资源</span><span class="hl-comment"></span><span class="hl-code">
 
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<hr>
<h2>文件和I/O</h2><p>
还有一些关于文件和I/O的类，我们也需要知道：</p>
<ul>
<li>
<a href="../java/java-file.html" target="_blank" rel="noopener">File Class(类)</a></li><li>
<a href="../java/java-filereader.html" target="_blank" rel="noopener">FileReader Class(类)</a></li><li>
<a href="../java/java-filewriter.html" target="_blank" rel="noopener">FileWriter Class(类)</a></li></ul>
<hr>
<h2>Java中的目录</h2>

<h3>创建目录：</h3><p>
File类中有两个方法可以用来创建文件夹：</p>
<ul>
<li>
		<strong>mkdir( )</strong>方法创建一个文件夹，成功则返回true，失败则返回false。失败表明File对象指定的路径已经存在，或者由于整个路径还不存在，该文件夹不能被创建。</li>
	<li>
		<strong>mkdirs()</strong>方法创建一个文件夹和它的所有父文件夹。</li>
</ul>
<p>
下面的例子创建 "/tmp/user/java/bin"文件夹：</p>
<div class="example">
<h2 class="example">CreateDir.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.</span><span class="hl-identifier">File</span><span class="hl-code">;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">CreateDir</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">dirname</span><span class="hl-code"> = </span><span class="hl-quotes">&quot;</span><span class="hl-string">/tmp/user/java/bin</span><span class="hl-quotes">&quot;</span><span class="hl-code">;
        </span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">d</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-identifier">dirname</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-comment">//</span><span class="hl-comment"> 现在创建目录</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-identifier">d</span><span class="hl-code">.</span><span class="hl-identifier">mkdirs</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>编译并执行上面代码来创建目录 "/tmp/user/java/bin"。
</p><p><strong>注意：</strong> Java 在 UNIX 和 Windows 自动按约定分辨文件路径分隔符。如果你在 Windows 版本的 Java 中使用分隔符 (/) ，路径依然能够被正确解析。
</p><hr>
<h2>读取目录</h2>
<p>
一个目录其实就是一个 File 对象，它包含其他文件和文件夹。
</p><p>如果创建一个 File 对象并且它是一个目录，那么调用 isDirectory() 方法会返回 true。
</p><p>可以通过调用该对象上的 list() 方法，来提取它包含的文件和文件夹的列表。
</p><p>下面展示的例子说明如何使用 list() 方法来检查一个文件夹中包含的内容：</p>
<div class="example">
<h2 class="example">DirList.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.</span><span class="hl-identifier">File</span><span class="hl-code">;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">DirList</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">dirname</span><span class="hl-code"> = </span><span class="hl-quotes">&quot;</span><span class="hl-string">/tmp</span><span class="hl-quotes">&quot;</span><span class="hl-code">;
        </span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f1</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-identifier">dirname</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">f1</span><span class="hl-code">.</span><span class="hl-identifier">isDirectory</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">目录 </span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">dirname</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">s</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> = </span><span class="hl-identifier">f1</span><span class="hl-code">.</span><span class="hl-identifier">list</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
            </span><span class="hl-reserved">for</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">i</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">; </span><span class="hl-identifier">i</span><span class="hl-code"> &lt; </span><span class="hl-identifier">s</span><span class="hl-code">.</span><span class="hl-identifier">length</span><span class="hl-code">; </span><span class="hl-identifier">i</span><span class="hl-code">++</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                </span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-identifier">dirname</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string">/</span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">s</span><span class="hl-brackets">[</span><span class="hl-identifier">i</span><span class="hl-brackets">]</span><span class="hl-brackets">)</span><span class="hl-code">;
                </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-code">.</span><span class="hl-identifier">isDirectory</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                    </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">s</span><span class="hl-brackets">[</span><span class="hl-identifier">i</span><span class="hl-brackets">]</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> 是一个目录</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
                </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">else</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                    </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">s</span><span class="hl-brackets">[</span><span class="hl-identifier">i</span><span class="hl-brackets">]</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> 是一个文件</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
                </span><span class="hl-brackets">}</span><span class="hl-code">
            </span><span class="hl-brackets">}</span><span class="hl-code">
        </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">else</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-identifier">dirname</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> 不是一个目录</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-brackets">}</span><span class="hl-code">
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>以上实例编译运行结果如下：</p>
<pre>
目录 /tmp
bin 是一个目录
lib 是一个目录
demo 是一个目录
test.txt 是一个文件
README 是一个文件
index.html 是一个文件
include 是一个目录
</pre>
<hr>
<h2>删除目录或文件</h2>
<p>删除文件可以使用  <strong>java.io.File.delete()</strong> 方法。</p>
<p>以下代码会删除目录 <strong>/tmp/java/</strong>，需要注意的是当删除某一目录时，必须保证该目录下没有其他文件才能正确删除，否则将删除失败。</p>
<p>测试目录结构：</p>
<pre>
/tmp/java/
|-- 1.log
|-- test
</pre>
<div class="example">
<h2 class="example">DeleteFileDemo.java 文件代码：</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">import</span><span class="hl-code"> </span><span class="hl-identifier">java</span><span class="hl-code">.</span><span class="hl-identifier">io</span><span class="hl-code">.</span><span class="hl-identifier">File</span><span class="hl-code">;
 
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">DeleteFileDemo</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-comment">//</span><span class="hl-comment"> 这里修改为自己的测试目录</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">folder</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">File</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">/tmp/java/</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-identifier">deleteFolder</span><span class="hl-brackets">(</span><span class="hl-identifier">folder</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
 
    </span><span class="hl-comment">//</span><span class="hl-comment"> 删除文件及目录</span><span class="hl-comment"></span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">deleteFolder</span><span class="hl-brackets">(</span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">folder</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
        </span><span class="hl-identifier">File</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">files</span><span class="hl-code"> = </span><span class="hl-identifier">folder</span><span class="hl-code">.</span><span class="hl-identifier">listFiles</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
        </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">files</span><span class="hl-code"> != </span><span class="hl-reserved">null</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
            </span><span class="hl-reserved">for</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">File</span><span class="hl-code"> </span><span class="hl-identifier">f</span><span class="hl-code"> : </span><span class="hl-identifier">files</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-code">.</span><span class="hl-identifier">isDirectory</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                    </span><span class="hl-identifier">deleteFolder</span><span class="hl-brackets">(</span><span class="hl-identifier">f</span><span class="hl-brackets">)</span><span class="hl-code">;
                </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">else</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
                    </span><span class="hl-identifier">f</span><span class="hl-code">.</span><span class="hl-identifier">delete</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
                </span><span class="hl-brackets">}</span><span class="hl-code">
            </span><span class="hl-brackets">}</span><span class="hl-code">
        </span><span class="hl-brackets">}</span><span class="hl-code">
        </span><span class="hl-identifier">folder</span><span class="hl-code">.</span><span class="hl-identifier">delete</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
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    <span class="mw-headline" id="qa_headline">5  篇笔记</span>
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<div id="postcomments"  style="display:none;" >
	<ol class="commentlist">
		<li class="comment even thread-even depth-1" id="comment-29433"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;童帅的二叔</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;120***7857@qq.com</p></div><div id="runoobvote-id-29433" data-commid = "29433" class="upvotejs"><a class="upvote"></a> <span class="count">164</span></div></div><div class="comt-main" id="div-comment-29433"><p>自己写了一个简单的小程序用来剪辑特定长度的音频，并将它们混剪在一起，大体思路是这样的：</p>

<p>1. 使用 FileInputStream 输入两个音频</p>
<p>2. 使用 FileInputStream的skip(long n) 方法跳过特定字节长度的音频文件，比如说：输入 skip(1024*1024*3)，这样就能丢弃掉音频文件前面的 3MB 的内容。</p>
<p>3. 截取中间特定长度的音频文件：每次输入 8KB 的内容，使用 count 记录输入次数，达到设置的次数就终止音频输入。比如说要截取 2MB 的音频，每次往输入流中输入 8KB 的内容，就要输入 1024*2/8 次。</p>
<p>4. 往同一个输出流 FileOutputStream 中输出音频，并生成文件，实现音频混合。</p>
<p>音乐素材下载：<a class="download" download href="..//static.runoob.com/download/demomusic-java.zip" rel="nofollow"> Download</a></p>
<p>下面就给出相关代码：</p>

<pre>public class MusicCompound 
{
    public static void main(String args[])
    {
        FileOutputStream fileOutputStream = null;
        FileInputStream fileInputStream = null;
        String fileNames[] = {"E:/星月神话.mp3","E:/我只在乎你.mp3"};
        //设置byte数组，每次往输出流中传入8K的内容
        byte by[] = new byte[1024*8];
        try
        {
            fileOutputStream = new FileOutputStream("E:/合并.mp3");
            for(int i=0;i&lt;2;i++)
            {
                int count = 0;
                fileInputStream = new FileInputStream(fileNames[i]);
                //跳过前面3M的歌曲内容
                fileInputStream.skip(1024*1024*3);
                while(fileInputStream.read(by) != -1)
                {                    
                    fileOutputStream.write(by);
                    count++;
                    System.out.println(count);
                    //要截取中间2MB的内容，每次输入8k的内容，所以输入的次数是1024*2/8
                    if(count == (1024*2/8))
                    {
                        break;
                    }
                }
            }
        }
        catch(FileNotFoundException e)
        {
            e.printStackTrace();
        }
        catch(IOException e)
        {
            e.printStackTrace();
        }
        finally
        {
            try
            {
                //输出完成后关闭输入输出流
                fileInputStream.close();
                fileOutputStream.close();
            } 
            catch(IOException e)
            {
                e.printStackTrace();
            }
        }
    }
}</pre>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">童帅的二叔</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;童帅的二叔</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;120***7857@qq.com</p></div></span>5年前 (2018-07-11)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-36088"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;乔乔</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;287***2758@qq.com</p></div><div id="runoobvote-id-36088" data-commid = "36088" class="upvotejs"><a class="upvote"></a> <span class="count">43</span></div></div><div class="comt-main" id="div-comment-36088"><p data-title="Java 列出目录下指定类型的文件">有时需要列出目录下指定类型的文件，例如：. java、. txt 等扩展名的文件。可以使用File类的下述两个方法，列出指定类型的文件：</p>
<ul><li>
1、<strong>public String[ ] list(FilenameFilter obj)</strong> 该方法用字符串的形式返回目录下的指定类型的所有文件
</li><li>
2、<strong>public File[ ] listFile(FilenameFilter obj)</strong> 该方法用 File 对象形式返回目录下的指定类型的所有文件
</li></ul>
<p>上述两个方法的参数 FilenameFilter 是一个接口，该接口有一个方法：</p>

<pre>public boolean accept(File f,String name);</pre>

<p>File 对象 f 调用 list 方法时，需向该方法传递一个实现 FilenameFilter 接口的对象，list 方法执行时，参数 obj 不断回调接口方法accept(File f,String name)，该方法中的参数 f 为，调用 list 的当前目录，参数 name 被实例化为当前目录中的一个文件名，当接口方法返回 true 时，list 方法就将名字为 name 的文件存放到返回的数组中。</p>

<pre>import java.io.*;

public class Filelei implements FilenameFilter {//此次使用本类作为接口

    /**
     * @param args
     */
    public void f(){
        File f=new File("E:\\Myworkspace\\08\\src");
        String []filename=f.list();//以字符串的形式，先列出当前目录下所有文件看一下（有什么类型的文件）
        for(int i=0;i&lt;filename.length;i++){
            System.out.println(filename[i]);
        }
        System.out.println("********************************");
        String []fname=f.list(this);
        for(int i=0;i&lt;fname.length;i++){
            System.out.println(fname[i]);
        }
        
    }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        new Filelei().f();
        
    }

    @Override
    public boolean accept(File f, String name) {//重写接口方法
        // TODO Auto-generated method stub
        return name.endsWith(".java");//返回当前目录下以.java结尾的文件
    }
}</pre>

<p>运行结果：</p>

<pre>A.java
B.java
C.java
J1.java
J2.java
J3.java
我是 DOC 文档.doc
我是 XLS 工作表.xls
我是文本文档.txt
********************************
A.java
B.java
C.java
J1.java
J2.java
J3.java</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/36088">乔乔</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;乔乔</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;287***2758@qq.com</p></div></span>5年前 (2018-10-20)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-39444"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;luffysman</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;N92***5465@stu.xjtu.edu.cn</p></div><div id="runoobvote-id-39444" data-commid = "39444" class="upvotejs"><a class="upvote"></a> <span class="count">36</span></div></div><div class="comt-main" id="div-comment-39444"><p>FileOutputStream 读写文件举例中出现乱码, 跟字符集编码无关, 是由于读写的格式不同导致的。</p>

<pre>// 读写文件, 以二进制读写, 有乱码, 是由于输入输出格式转换的原因, 和字符集编码方式无关
public static void main(String[] args) {
    try { 
        byte[] bWrite = {11, 21, 3, 40, 5 };    
        OutputStream os = new FileOutputStream("./out/test.txt");   
        for (int x = 0; x &lt; bWrite.length; ++x) {  
            os.write(bWrite[x]);  
        }       
        os.close();   
        InputStream is = new FileInputStream("./out/test.txt");      
        int size = is.available();    
        for (int x = 0; x &lt; size; ++x) {   
            System.out.print((byte) is.read() + " ");    //强转为byte类型就好了  
        }  
        is.close();   
    } catch (IOException e) {  
        System.out.print("Exception");
    }
}</pre>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">luffysman</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;luffysman</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;N92***5465@stu.xjtu.edu.cn</p></div></span>4年前 (2019-01-30)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-40704"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;iamanoob</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;599***619@qq.com</p></div><div id="runoobvote-id-40704" data-commid = "40704" class="upvotejs"><a class="upvote"></a> <span class="count">20</span></div></div><div class="comt-main" id="div-comment-40704"><p>BufferedReader 是支持同步的，而 Scanner 不支持。如果我们处理多线程程序，BufferedReader 应当使用。</p>

<p>BufferedReader 相对于 Scanner 有足够大的缓冲区内存。</p>

<p>Scanner 有很少的缓冲区(1KB 字符缓冲)相对于 BufferedReader(8KB字节缓冲)，但是这是绰绰有余的。</p>

<p>BufferedReader 相对于 Scanner 来说要快一点，因为 Scanner 对输入数据进行类解析，而 BufferedReader 只是简单地读取字符序列。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">iamanoob</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;iamanoob</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;599***619@qq.com</p></div></span>4年前 (2019-03-13)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-42882"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;sky-wu</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;Wu_***@Foxmail.com</p></div><div id="runoobvote-id-42882" data-commid = "42882" class="upvotejs"><a class="upvote"></a> <span class="count">17</span></div></div><div class="comt-main" id="div-comment-42882"><p>使用 io 流进行文件的简单复制:</p>
<p>test.txt 内容为：</p>

<pre>I love Java,  I love JavaI love Java,  I love JavaI love Java,  I love JavaI love Java,  I love JavaI love Java,  I love Java</pre>
<p>代码：</p>
<pre>import java.io.*;

public class Test {
    public static void main(String[] args) {
        File sourcefile = new File("./test.txt");
        File copyfile = new File("./testcopy.txt");
        FileInputStream fileInputStream = null;// 从文件中读数据
        FileOutputStream fileOutputStream = null;// 用于把数据写入文件
        BufferedWriter bufferedWriter = null;// 用于把数据写入文件
        try {
            if (!sourcefile.exists()) {
                sourcefile.createNewFile();
                bufferedWriter = new BufferedWriter(new FileWriter(sourcefile));
                // bufferedwriter 自动追加数据
                String s = new String(" I love Java");

                char bchar[] = s.toCharArray();
                for (int i = 0; i &lt; 5; i++) {
                    // 两种方式往文件中写数据
                    bufferedWriter.write(bchar, 0, bchar.length);
                    bufferedWriter.write(", " + s + "\n");
                }
                // 写完之后才能关闭流,
                bufferedWriter.flush();
                bufferedWriter.close();
            }
            copyfile.createNewFile();
            fileInputStream = new FileInputStream(sourcefile);
            fileOutputStream = new FileOutputStream(copyfile);
            byte b[] = new byte[8192];
            int len = b.length;
            while ((len = fileInputStream.read(b, 0, len)) &gt; 0) {
                fileOutputStream.write(b, 0, len);
                fileOutputStream.flush();
            }
            System.out.println("file copied");
            fileInputStream.close();
            fileOutputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}</pre>



<p>执行程序，可以看到创建了一个 testcopy.txt 文件，内容为：</p>

<pre>I love Java,  I love JavaI love Java,  I love JavaI love Java,  I love JavaI love Java,  I love JavaI love Java,  I love Java</pre>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">sky-wu</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;sky-wu</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;Wu_***@Foxmail.com</p></div></span>4年前 (2019-05-18)</div></div></li><!-- #comment-## -->
	</ol>
	<div class="pagenav">
			</div>
</div>
<div id="respond" class="no_webshot"> 
		<div class="comment-signarea" style="display:none; padding: 20px 20px;"> 
	<h3 class="text-muted" id="share_code" style="color: #799961;"><i class="fa fa-pencil-square-o" aria-hidden="true"></i> 点我分享笔记</h3>
	<!--
	<p style="font-size:14px;">笔记需要是本篇文章的内容扩展！</p><br>
	<p style="font-size:12px;"><a href="../tougao" target="_blank">文章投稿，可点击这里</a></p>
	<p style="font-size:14px;"><a href="../w3cnote/runoob-user-test-intro.html#invite" target="_blank">注册邀请码获取方式</a></p>
		<h3 class="text-muted"><i class="fa fa-info-circle" aria-hidden="true"></i> 分享笔记前必须<a href="javascript:;" class="runoob-pop">登录</a>！</h3>
		<p><a href="../w3cnote/runoob-user-test-intro.html#invite" target="_blank">注册邀请码获取方式</a></p>-->
	</div>
		
	<form action="/wp-content/themes/runoob/option/addnote.php" method="post" id="commentform" style="display:none;">
		<div class="comt">
			<div class="comt-title">
				<i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i>				<p><a id="cancel-comment-reply-link" href="javascript:;">取消</a></p>
			</div>
			<div class="comt-box">
			<div id="mded"></div>
			
				<div class="comt-ctrl">
					<div class="comt-tips"><input type='hidden' name='comment_post_ID' value='5012' id='comment_post_ID' />
<input type='hidden' name='comment_parent' id='comment_parent' value='0' />
</div>
					<button type="submit" name="submit" id="submit" tabindex="5"><i class="fa fa-pencil" aria-hidden="true"></i> 分享笔记</button>
				</div>
			</div>
		
				
					<div class="comt-comterinfo"> 
						<ul id="comment-author-info">
							<li class="form-inline"><label class="hide" for="author">昵称</label><input class="ipt" type="text" name="author" id="author" value="" tabindex="2" placeholder="昵称"><span class="text-muted">昵称 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="email">邮箱</label><input class="ipt" type="text" name="email" id="email" value="" tabindex="3" placeholder="邮箱"><span class="text-muted">邮箱 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="url">引用地址</label><input class="ipt" type="text" name="url" id="url" value="" tabindex="4" placeholder="引用地址"><span class="text-muted">引用地址</span></li>
						</ul>
					</div>
				
			
		</div>

	</form>
	</div>
<script type="text/javascript">
$(function() {
	//初始化编辑器
	
	var editor = new Simditor({
	  textarea: $('#mded'),
	  placeholder: '写笔记...',
	  upload:false,
	 // upload: {url:'/api/comment_upload_file.php',params: null,fileKey: 'upload_file',connectionCount: 1,leaveConfirm: '文件正在上传，您确定离开?'},
	  defaultImage: 'https://www.runoob.com/images/logo.png',
	  codeLanguages: '',
	  autosave: 'editor-content',
	  toolbar: [  'bold','code','ul','ol','image' ]
	});
	editor.on('selectionchanged', function() {
		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});
	$("#user_add_note").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		$('html, body').animate({
       	    scrollTop: $("#respond").offset().top
    	}, 200);
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" style="display:none;" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  5012;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).children(".tooltip").removeAttr("style");
	});
	/*
	$(".wrapper i").hover(function(){
		$(this).siblings(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).siblings(".tooltip").css({ "opacity": 0, "pointer-events": "auto"});
	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 5012, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":5012},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

<link rel="stylesheet" href="../0/qa.css?1.44">
<link rel="stylesheet" type="text/css" href="../0/simditor.min.css" />
<script type="text/javascript" src=""></script>
<script type="text/javascript" src=""></script>
<script type="text/javascript" src=""></script>
<script type="text/javascript" src=""></script>
<script type="text/javascript" src=""></script>
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<style>	
.responsive_ad1 { display:none; }
@media(min-width: 800px) { .responsive_ad1 {  display:block;margin:0 auto;} }
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<script async src=""
     crossorigin="anonymous"></script>
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<ins class="adsbygoogle"
     style="display:block"
     data-ad-client="ca-pub-5751451760833794"
     data-ad-slot="1691338467"
     data-ad-format="auto"
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    line-height: 1.5em;
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